Cardiovascular disease (CVD) remains the nation's major killer and largest single source of health expenditures. The impact of CVD mortality and morbidity is particularly notable with advancing age. Included among the factors identified as contributory to risk is the level of regular physical activity individuals engage in. The association between physical activity and CVD has been noted for older as well as younger populations. The identification of physical activity as a plausible method for positively influencing physiological as well as behavioral and psychological responses to stress presents one potential mechanism through which the association between regular activity and CVD risk may be at least partly mediated. While the relatively few controlled studies of the effects of aerobic activity on stress-related response are encouraging, a number of dimensions remain virtually unexplored, including the study of responses in the natural environment and the use of promising home-based activity interventions for generating sustained exercise adherence. In addition to cardiovascular disease, a relationship between physical activity and stress-related response has implications for issues related to enhancement of daily function and quality of life in older adults. Yet to undertake a comprehensive inquiry of the effects of physical activity on stress-related response, an understanding of biomedical as well as behavioral and psychological processes associated with each is needed. The purpose of the proposed course of training and research is to take advantage of the unique resources at Stanford University in obtaining systematic training in biomedical areas of particular relevance to the exercise and stress fields. Stanford faculty with expertise in cardiovascular function and assessment, exercise physiology, neuroendocrinology, carbohydrate metabolism, and aging will serve as specialty advisors in directing the course of the training. This training will then be applied in the development and piloting of physiological, behavioral, and psychological measures of stress-related response, occurring in both laboratory and natural settings, in an older adult population (ages 50-70). The specific aims of the pilot work are to develop laboratory-based stress-related stimulus conditions that are relevant for and acceptable to an older population; to pilot laboratory- based and natural setting protocols for measuring the 3 modalities of stress-related response in older adults; and to determine effect sizes for the measures under investigation with respect to the target population. The testing and measurement procedures developed during this proposal will subsequently be applied in a larger project proposal aimed at assessing the short- and longer-term effects of physical activity on physiological, behavioral, and psychological responses to stress in this population.